I don't have a block in the back. The rear is at factory height. It was exactly level when the coilovers were new and now it is very slightly lower in the front. I don't currently tow but do haul dirt bikes and mountain bikes and it never really squats. I like the lower bed height for loading. I'm planning to get some air bags for the back if I need to tow or haul something heavier on a regular basis.
Fox said you can mount the 2.0 shocks in any position.